N:dlzc D:aol T:com (dlzc) wrote:
Maybe my description was unclear. I'll try again:
We are (not necessarily) at the equator. There is
a hollow sphere with bearings on the outside so
it can rotate with its axis parallell to earths axis.

This cannot be entirely true, if you are going to
remove energy from the gyro.

On the inside of the equator of the sphere there
are 2 bearings that hold a gyro so it will spin
perpendicular to the spheres axis. Now there is
no way the gyro can align its axis with earths
*current* axis, whether I extract energy or not.

Then you will get no energy out.

But the gyro will resist to changing its axis and
this torque can be used to extract energy.

If you remove energy, then you alter the gyro's axis of rotation.

Quote:

If the axes must align then why shouldn't earths axis change -
just a tiny bit?

A fly crashes into the Earth. Will the Earth then fall into the
Sun? The change will be to the gyro's axis of rotation, and you
won't be able to detect a change in Earth's.

Quote:

Use a moon. Create a tidal generator.

How would I do that? I don't like using the tides
of the sea because I think that's to unreliable.
The facility should remain operable even if human maintainance
is absent for decades or
centuries.

Better still orbit Pluto or Charon. Plenty cold there, all
the time.
Not too many vandals either.

Yep, that might be an option. But the bodies
must be protected from cosmic rays and
asteroids which would mean heavy armor
which makes the trip quite costly. Also
maintainence is rather difficult. OTOH I see
the average temperature is 50 K so there
isn't really a need for maintainence. Landing
on Pluto should be feasible once we are
there and digging a hole might be possible
to protect from rays and asteroids. The density of Pluto is
only 1.1 g/cm3.

But then I guess it would probably take
quite long until someone came there to
revive us.

Panspermia. Grind the bodies up and spray them into the heavens.
Interstellar travel.

Quote:

Since these bodies are already dead, what
does "safe" mean?

Cryopreserving a body shouldn't kill.

It does. Anaesthesia for more than 8 hours, yields a greater
than 50% probability that the patient will die anyway within a
year. Anaesthetised for centuries?

Quote:

It should preserve the information that makes
up the mind so it can be scanned later and
emulated in a computer or robot. So asteroids,
cosmic rays, heat, vandals, whatever must be
prevented from destroying the body/brain.

Maybe my description was unclear. I'll try again:
We are (not necessarily) at the equator. There is
a hollow sphere with bearings on the outside so
it can rotate with its axis parallell to earths axis.

This cannot be entirely true, if you are going to remove energy
from the gyro.

On the inside of the equator of the sphere there
are 2 bearings that hold a gyro so it will spin
perpendicular to the spheres axis. Now there is
no way the gyro can align its axis with earths *current* axis,
whether I extract energy or not.

Then you will get no energy out.

But the gyro will resist to changing its axis and this torque can be
used to extract energy. If the axes must align then why shouldn't earths
axis change - just a tiny bit?

Quote:

Use a moon. Create a tidal generator.

How would I do that? I don't like using the tides of the sea because I
think that's to unreliable. The facility should remain operable even if
human maintainance is absent for decades or centuries.

Quote:

Better still orbit Pluto or Charon.
Plenty cold there, all the time.
Not too many vandals either.

Yep, that might be an option. But the bodies must be protected from
cosmic rays and asteroids which would mean heavy armor which makes the
trip quite costly. Also maintainence is rather difficult. OTOH I see the
average temperature is 50 K so there isn't really a need for
maintainence. Landing on Pluto should be feasible once we are there and
digging a hole might be possible to protect from rays and asteroids. The
density of Pluto is only 1.1 g/cm3.

But then I guess it would probably take quite long until someone came
there to revive us.

Quote:

Since these bodies are already dead, what does "safe" mean?

Cryopreserving a body shouldn't kill. It should preserve the information
that makes up the mind so it can be scanned later and emulated in a
computer or robot. So asteroids, cosmic rays, heat, vandals, whatever
must be prevented from destroying the body/brain.

N:dlzc D:aol T:com (dlzc) wrote:
I thought about mentioning that. But ... say we
are at the equator. The gyro's axis initially is
vertical and is mounted in a hollow sphere. The
sphere's axis is mounted horizontally with a
north-south orientation. Now the gyro's axis will
remain perpendicular to earth's axis.

No, it will not. Not if you are going to remove
energy from the system.

But this means that earths axis will change until
it is aligned with the gyro.

No. It means the gyro's axis will be altered to match the
Earth's. The fly will move.. not (much) the mountain.

Quote:

Certainly a long order process.

Depends on your rate of energy removal. Suffice it to say that
if it is on the order of the rate you put energy in to get the
gyro up to speed, it'll be on the same order before the gyro puts
out no more useful amount of energy.

Quote:

Maybe my description was unclear. I'll try again:
We are (not necessarily) at the equator. There is
a hollow sphere with bearings on the outside so
it can rotate with its axis parallell to earths axis.

This cannot be entirely true, if you are going to remove energy
from the gyro.

Quote:

On the inside of the equator of the sphere there
are 2 bearings that hold a gyro so it will spin
perpendicular to the spheres axis. Now there is
no way the gyro can align its axis with earths *current* axis,
whether I extract energy or not.

Then you will get no energy out.

Quote:

Now I wonder what dimensions such a
generator must have if it is to deliver 10 kW
power. Top priority is reliability because the
intended purpose is to support a facility that
preserves humans at cryogenic temperatures.
I guess it will be unpractical because it has
too heavy and too many moving parts.

Use a moon. Create a tidal generator. Better still orbit Pluto
or Charon. Plenty cold there, all the time. Not too many
vandals either.

Quote:

Otherwise it would be an interesting option because the
facility could be buried and
sealed deeply underground. Safe from nukes
or casual vandals. The currently best option
IMO are solar powered thermoelectric elements.

I thought about mentioning that. But ... say we
are at the equator. The gyro's axis initially is
vertical and is mounted in a hollow sphere. The sphere's axis
is mounted horizontally with a
north-south orientation. Now the gyro's axis will
remain perpendicular to earth's axis.

No, it will not. Not if you are going to remove energy from the
system.

But this means that earths axis will change until it is aligned with the
gyro. Certainly a long order process.

Maybe my description was unclear. I'll try again:
We are (not necessarily) at the equator. There is a hollow sphere with
bearings on the outside so it can rotate with its axis parallell to
earths axis. On the inside of the equator of the sphere there are 2
bearings that hold a gyro so it will spin perpendicular to the spheres
axis. Now there is no way the gyro can align its axis with earths
*current* axis, whether I extract energy or not.

Now I wonder what dimensions such a generator must have if it is to
deliver 10 kW power. Top priority is reliability because the intended
purpose is to support a facility that preserves humans at cryogenic
temperatures. I guess it will be unpractical because it has too heavy
and too many moving parts. Otherwise it would be an interesting option
because the facility could be buried and sealed deeply underground. Safe
from nukes or casual vandals. The currently best option IMO are solar
powered thermoelectric elements.

Is it possible to build an electricity generator that
is driven by the relative rotation between a gyro
and earths rotation with their axes being
perpendicular?

Yes. But to gain energy from it, you will be
altering the rotation of the gyro. In short order,
you will have the gyro's axis parallel with Earth's
rotation axis... and energy production stops.

I thought about mentioning that. But ... say we
are at the equator. The gyro's axis initially is
vertical and is mounted in a hollow sphere. The sphere's axis
is mounted horizontally with a
north-south orientation. Now the gyro's axis will
remain perpendicular to earth's axis.

No, it will not. Not if you are going to remove energy from the
system.

Quote:

Maybe there will be some change of earth's
precession, but I'm not worried about that.
Hopefully it will not cause major earth quakes or climate
changes. Could we choose to either
increase or decrease earths precession?

Is it possible to build an electricity generator that
is driven by the relative rotation between a gyro
and earths rotation with their axes being
perpendicular?

Yes. But to gain energy from it, you will be altering the
rotation of the gyro. In short order, you will have the gyro's
axis parallel with Earth's rotation axis... and energy production
stops.

I thought about mentioning that. But ... say we are at the equator. The
gyro's axis initially is vertical and is mounted in a hollow sphere. The
sphere's axis is mounted horizontally with a north-south orientation.
Now the gyro's axis will remain perpendicular to earth's axis.

Maybe there will be some change of earth's precession, but I'm not
worried about that. Hopefully it will not cause major earth quakes or
climate changes. Could we choose to either increase or decrease earths
precession?

Is it possible to build an electricity generator that is driven by the
relative rotation between a gyro and earths rotation with their axes
being perpendicular? Would it be hard to get enough power to overcome
friction and get some surplus power? I guess because it rotates only
once per day it would be practical to lift a weight and turn its
potential energy into electricity every now and then rather than using a
direct generator or a speed up gear.